Definitions
Informal Definition
An Intelligent Transport System (ITS) Architecture is a set of high level views that enable plans to be made for integrating ITS applications and services. It normally covers technical aspects, plus the related organisational, legal and business issues.
ITS Architectures can be created at national, regional or city level, or relate to specific sectors or services. They help to ensure that the resulting ITS deployment:
- can be planned in a logical manner;
- integrates successfully with other systems;
- meets the desired performance levels;
- has the desired behaviour;
- is easy to manage;
- is easy to maintain;
- is easy to extend;
- satisfies the expectations of the users.
Formal Definition
An ITS architecture is the conceptual design that defines the structure and/or behavior of an integrated Intelligent Transport System (ITS).
An architecture description is a formal description of a system, organized in a way that supports reasoning about the structural properties of the system. It defines the system components or building blocks and provides a plan from which products can be procured, and systems developed, that will work together to implement the overall system. This may enable one to manage investment in a way that meets business needs.
Technical Definition
Thus an ITS Architecture is:
- a top-level framework;
- a strategic plan for designs;
- non-deterministic;
- it states “What is needed” and not “How it is to be implemented”;
- it is technology independent;
- the life-time of an ITS Architecture is normally longer than any particular technology;
- a set of top-level assumptions;
- the minimun necessary not the maximum possible.
Why you need an ITS Architecture?
Like other highly complex systems, integrated ITS applications need a strategic framework as a basis for choices concerning their design and deployment, as well as for investment decisions. Such a framework is generally called a System Architecture.
An Intelligent Transport System Architecture will need to cover technical aspects, plus the related organisational, legal and business issues.
ITS Architectures can be created at national, regional or city level, or relate to specific sectors or services. They help to ensure that the resulting ITS deployment:
- can be planned in a logical manner;
- integrates successfully with other systems;
- meets the desired performance levels;
- has the desired behaviour;
- is easy to manage;
- is easy to maintain;
- is easy to extend;
- satisfies the expectations of the users.
The ability to integrate systems greatly increases their potential. By complying with the European ITS Framework Architecture, not only will applications work together, but they can be made inter-operable at a European level, a feature of growing importance.
Inter-operability encompasses the technical, operational and organisational aspects, and implies the harmonious and complementary functioning of the overall system.
The benefits of integrated ITS – an example:
There has been a serious accident on the city ring road. It is just after 8am and there is already congestion involving commuters coming into the city. The traffic control centre needs to be able to:
- identify the nature ot the accident;
- ensure that the appropriate emergency services are alerted;
- give emergency vehicles priority at traffic signals;
- keep other traffic away from the accident;
- inform public transport operations about the incident;
- arrange diversions and advise drivers on all roads and motorways;
- inform pre-trip travellers, so they can adjust their plans.
To co-ordinate these tasks efficiently, there must be a rapid and reliable flow of information between all the systems involved. This flow can be speeded up significantly if the systems are integrated, i.e. if data is exchanged automatically between motorway and city control centres, if the information is available to public transport operators and users as well as to private car drivers, and can be sent to message panels, on-board vehisle systems, mobile phones, web-based transport informations services, etc.
In this example, system integration can make it possible not only to minimise travel disruption, but also to save lives.